In recent years, it has become fashionable to collect pins, particularly pins indicating that the wearer has an association with or attended specific events. For example, pins are used as promotional items at baseball games, they are openly and widely traded at the Olympic Games, etc. In the pins known generally in the prior art, the entire intrinsic value of the pin is due to certain characteristic ornamentations on the pin itself. For example, in the baseball context, the pin may show the logo of an All-Star Game. In another example, the pin may show the logo of a corporate sponsor and certain indicia or ornamentations that represent an event, such as the Olympic Games. In many of these prior art situations, the pins are not necessarily individual, since the issuer of the pins may have a series of different pins available. However, the pins themselves do not interact with each other in any manner. As a result, if the pins are collected together and displayed simultaneously, they really present nothing more than the indication that the owner has successfully completed the set. In fact, unless one knows exactly how many pins are available in the set, it is not inherently obvious to an observer whether the collector has obtained the entire set.